Dynamo-electric machine.



J. LE G. DAVIfi. 111mm ELECTRIC MACHINE. APPLICATION TILED DEO.14 1908.

969,608 1 Patented Sep1;.6,1910

V VlTNE S SE: INVENTOR I Mgigw I BY 1 ATTORNEY UNITED STATES-PATENT OFFICE.

JOSEPH: LE CONTE DAVIS, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING- noose ELECTRIC & MANUFACTURING COMPANY, A. oonronn rzon 0F PnivNsYL- VAN IA.

DYNAMo-Emo'rmo MACHINE.

Patented Sept. 6, 1910.

Application filed December 14, 1908. Serial No. 467,476.

To all itmay concern:

Be it known that I, JOSEPH LE C. DAVIS,

a citizen of the United States, and a resident of. Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented anew and useful Improvement in Dynamol llectrie.l.\ achines, of which the to lowing is a specification.

My inventionrelates to dynamo-electric machines and ithas special reference to such machines as .are provided with auxiliary windings for opposing armature reaction and for creating a commutating field.

The object of my invention-is to provide an' improved field structure, embodying windings of the class above indicated, that shall be simple in construction and effective in operation.

Railway motors and other dynan'io-el'cctric machines ha \'0 frequently been provided with auxiliary poles aml windings between the main poles for the pnrpose of improving the commutation of the machine. In some cases, the intermediate poles and windings have been either replaced or supplemented I by interpolar demagnetizing windings disposed in cross slots in the faces of the main polar projections. 1 v

According to my present invention, I pro-' vide removable extensions for the main polar projections having cross slots that are open at the sides which fit against the ends of the polar projections in order that complete auxiliary coils may be readily inserted in the 1ion-mirresptmding slots in adjacent extensions and then be supported in operative relation to other parts bymcrclyclamping lho extensions against the ends of the polar projections.

l'he single figure of the accompanying dra ning is a view partially in section and partially in elevation of a portion of the field magnet of a dynamo-electric machine (-|nl1o(l \'in my invention.

Referring to the drawing, the structure illustrated comprises a. field magnet frame 1 havi'ngra plurality of main polar u'ojcclions Z and auxiliary polar projections 4. The main polar projections 2 are provided with magnetizing windings 3 and extensions 3 having cross slots 6 which open' into the dividing surfaces betwcim thccxtcnsionsand [he faces of the main polar projections. 'lhc extensions are held iniposition by bolts 7 which extend inwardly from the outer-surface of the frame. The auxiliary or'intcrinediate polar projection 4 is rovided witha [coil 8 and is secured to the means of bolts 9. The machine is provided with demagnetizing coils 10 which are disposed in the slots 6 ofadjacent poles;

The fact that the polar extensions '5 are detachably secured to the main polar projections 2 is of special importance since it permits of the use of so called formed coils which are wound and insulated before they are assemblcd'in position. Since the slots- 6- open into the inner surface of the extension 5, the necessity for holding the coils 10 in position by separate supports or braces is obviatedQthe extensions themselves, when bolted to the ends of the polar pro jections, serving as a means for efficiently supporting the coils.

It may be found desirable, in some cases, to provide narrow slots or saw cuts 11 between the out-er endsof the slots 6 and-the outer faces of the extensions in order to obrame by tain partially closed, instead of entirely closed, slots for the coils 10.

\Vhile I have illustrated m'y improved field .rnagnct structure and interpolar winding as associated with auxiliary or intermediate poles and coils, I desire that my in ention shall not be restricted to this combination and that only such limitations shall be imposed as are indicated in the appended claim. i

I claim as my invention:

dynamo-electric machine framc'lmving a plurality oi polar projections each of which comprises an integral l)aso. ])ort.ion and a cap or oxtcnsion rcmovably secured to the base portion and having laterally oxlcmling polo lips and cross slots, the Inner sidcs of which are closed by the face of the base portion, magnetizing windings for the polar projcctions, and demagnetizi'ng coils. the side portions of each of which are located in cross slots of adjacent polar project ions.

in testimony where-id, l have hereunto subscribed my name this 27th day of November, [90S JUSEII'I' Ll) (lONflll DAVIS.

W i lncsscs 

